Kumanthong literally means “Golden Child” in Thai. “Child” refers to the ghost kid while “Golden” refers to the gold leaves covering the effigy.
On the internet, many would say that Khun Paen was the first to create kumanthongs. This isn’t true as kumanthongs existed before Khun Paen was born.
The traditional way of making kumanthong involves surgically removing a dead fetus from the deceased mother and drying it over fire. The dried corpse would then be covered with gold leaves, hence the word “Golden Child”. The maker has to well-versed in magic so as to prevent the ghost mother from taking its child back and to prevent it from hurting the maker. Such methods are still practised illegally in rural parts of Thailand but the effigy is known as lukkok now instead of kumanthong. It is still not illegal to make lukkok from puppy or kitten corpses by roasting them over fire so cat or puppy lukkoks still exist. Kumanthongs are still more powerful than puppy or cat lukkoks.
Kumanthongs made using necromancy or dark arts would grow a lot faster than a living kid.